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The effect of ethanol fuel dilution on oil performance and MoDTC tribofilms formation and composition

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Friction 2024年第9期12卷 2108-2125页

作者： Juan RUIZ-ACERO felipe KESSLER Henara COSTA Tiago COUSSEAU Polytechnic School Universidade de São PauloSão Paulo 05508-030Brazil School of Food and Chemistry Universidade Federal do Rio GrandeRio Grande 96203-000Brazil School of Engineering Universidade Federal do Rio GrandeRio Grande 96203-900Brazil Mechanical Engineering Department Univ.Tecnológica Federal do ParanáCuritiba 81280-340Brazil University of Newcastle CallaghanSW 2308Australia

Ethanol has emerged as a promising alternative to fossil fuels,but its use can lead to significant dilution in lubricants,particularly during cold start or heavy *** dilution can affect the performance of additives,including friction modifiers like molybdenum dithiocarbamate(MoDTC),which are designed to reduce friction under extreme contact *** research suggests that ethanol may impact the performance of MoDTC,prompting this study’s goal to investigate the effects of ethanol on MoDTC tribofilms and their friction response under boundary lubrication ***,reciprocating tribological tests were performed with fully formulated lubricants containing MoDTC with varying ethanol *** results indicate that a critical ethanol dilution level inhibits friction reduction by MoDTC activation,resulting in friction coefficients(COFs)similar to the base *** tested with simple mixtures of polyalphaolefin(PAO)+MoDTC showed increased COFs with added *** of tested surfaces using Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),and X-ray absorption spectroscopy near the edge structure(XANES)revealed the presence of sulfates,MoO_(3),MoS_(2),and MoS_(x)O_(y)compounds in the tribofilms formed on the surfaces,with and without ethanol diluted in the ***,the addition of ethanol increased the sulfates and MoO_(3)content of the tribofilms at the expense of friction-reducing compounds such as MoS_(2)and MoS_(x)O_(y).These findings suggest that ethanol dilution in lubricants containing MoDTC creates an oxygen-rich interfacial medium that favors the formation of compounds with insufficient friction-reducing capabilities.

关键词： molybdenum dithiocarbamate(MoDTC) ethanol tribofilm friction modifier additive lubricant

Impact of STAT-signaling pathway on cancer-associated fibroblasts in colorectal cancer and its role in immunosuppression

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1705-1724页

作者： Damián Sánchez-Ramírez Mónica G Mendoza-Rodríguez Omar R Alemán Fernando A Candanedo-González Miriam Rodríguez-Sosa Juan JoséMontesinos-Montesinos Mauricio Salcedo Ismael Brito-Toledo felipe vac.-paniagua Luis I Terrazas Unidad de Investigacion en Biomedicina Facultad de Estudios Superiores IztacalaUniversidad Nacional Autonoma de MexicoTlalnepantla 54090Estado de MexicoMexico Department of Biology Facultad de QuimicaUniversidad Nacional Autonoma de MexicoCiudad UniversitariaMexico City 04510Mexico Department of Pathology National Medical Center Century XXIInstituto Mexicano del Seguro SocialMexico City 06720Mexico Laboratorio de Células Troncales Mesenquimales Unidad de Investigación Médica en Enfermedades OncológicasHospital de Oncología Centro Medico Nacional Siglo XXIInstituto Mexicano del Seguro SocialMexico City 06720Mexico Unidad de Investigacion en Biomedicina y Oncologia Genomica Instituto Mexciano del Seguro SocialMexico City 07300Mexico Servicio de Colon y Recto Hospital de Oncología Centro Medico Nacional Siglo XXIInstituto Mexicano del Seguro SocialMexico City 06720Mexico Laboratorio Nacional en Salud Facultad de Estudios Superiores IztacalaUniversidad Nacional Autónoma de MéxicoTlalnepantla 54090Estado de MexicoMexico

Colorectal cancer(CRC)remains one of the most commonly diagnosed and deadliest types of cancer *** displays a desmoplastic reaction(DR)that has been inversely associated with poor prognosis;less DR is associated with a better *** reaction generates excessive connective tissue,in which cancer-associated fibroblasts(CAFs)are critical cells that form a part of the tumor *** are directly involved in tumorigenesis through different ***,their role in immunosuppression in CRC is not well understood,and the precise role of signal transducers and activators of transcription(STATs)in mediating CAF activity in CRC remains *** the myriad chemical and biological factors that affect CAFs,different cytokines mediate their function by activating STAT signaling ***,the harmful effects of CAFs in favoring tumor growth and invasion may be modulated using STAT ***,we analyze the impact of different STATs on CAF activity and their immunoregulatory role.

关键词： Cancer-associated fibroblasts Signal transducer and activator of transcription signaling Colorectal cancer Immunity Immunosuppression

A prototype for on-site generation of chlorinated disinfectant for use in rural aqueducts

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Water Science and Engineering 2024年第1期17卷 33-40页

作者： Diana Marcela Cuesta Parra felipe Correa Mahecha Andrés felipe Rubio Pinzon Davidcamilo Ramirez Bustos Leonel Alveyro Teran Llorente Miguel Fernando Jimenez Jimenez Chemical and Environmental Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia Chemical Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia Mecanical Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia

Sodium hypochlorite has significant potential as a sanitation solution in hard-to-reach *** studies have investigated the optimal electrolysis parameters for its production with volumes greater than 1o *** study evaluated sodium hypochlorite production through electrolysis in a 22-L prototype and identified the optimal operating *** were performed using graphite electrodes with areas of 68.4 cm^(2) at the laboratory scale and 1865.0 cm^(2) at the prototype scale.A design for experiments with different operating times,chloride concentrations,and electric current intensities was *** optimal operating time,sodium chloride concentration,and current intensity at the laboratory scale were 120 min,150 g of chloride per liter,and 3 A,respectively,leading to the production of 5.02 g/L of the disinfectant with an energy efficiency of 12.21 mg of Cl_(2) per *** the prototype scale,the maximum sodium hypochlorite concentration of 3.99 g of chloride per liter was achieved with an operating time of 120 min,a sodium chloride concentration of 100 g of chloride per liter,and a current intensity of 70 A,reaching an energy efficiency of 42.56 mg of Cl_(2) per *** addition,this study evaluated the influences of the chloride concentration,current intensity,and operating time on the production of sodium hypochlorite at the two scales,and formulated the equations showing the trends of sodium hypochlorite production and energy efficiency in the electrochemical *** 22-L prototype model for production of this oxidizing substance is promising for disinfection of large volumes of water in areas that are difficult to access.

关键词： Disinfection Electrolysis Energy efficiency Optimization Sodium hypochlorite

Influence of biomass burning on ozone levels in the Megalopolis of Central Mexico during the COVID-19 lockdown

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Journal of Environmental Sciences 2024年第9期143卷 99-115页

作者： Victor Almanza Luis Gerardo Ruiz-Suárez Ricardo Torres-Jardón Agustín García-Reynoso Iván Y.Hernández-paniagua Institute for Atmospheric Sciences and Climate Change National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reductions in anthropogenic emissions resulting from the COVID-19 lockdown provided a unique opportunity to evaluate the effect of mitigation measures aiming to abate air *** Mexico,the total lockdown period took place during the dry-hot season when biomass burning activity is ***,we investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis of Central *** studied period covers the lockdown phases 2 and 3,and the first month of the New *** applied a factor separation technique and process analysis to estimate the pure and synergistic contributions of emission reductions under lockdown and that from biomass burning to daily ozone maximum concentrations in 7 metropolitan areas of different states in the *** results revealed that biomass burning plumes likely masked the effect of massive reductions from mobile emissions,impacted the PBL development during phase 3 and favored transition and mixed NO_(x)-limited and VOC-limited regional *** contributed to increased ozone production in the middle to lower PBL by changing the regional background levels which potentially could bias high ozone production efficiency *** the Megalopolis contribution to economic and societal development at national scale,our study suggests that ozone mitigation measures during the dry-hot season targeting mainly mobile emissions will likely be offset by biomass burning plumes.A regional and synergic policy aiming to control biomass burning would help to reduce the occurrence of high ozone levels in Central Mexico with the co-benefit of tackling short-lived climate pollutants.

关键词： COVID-19 Mexico Megalopolis Ozone Factor Separation Process Analysis

A review of torsional vibration mitigation techniques using active control and machine learning strategies

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Petroleum 2024年第3期10卷 411-426页

作者： Aditya Sharma Khizar Abid Saket Srivastava Andres felipe Baena Velasquez Catalin Teodoriu The University of Oklahoma NormanOKUSA

Drilling is one of the most challenging and expensive processes in hydrocarbon extraction and geothermal well *** faced during drilling can increase the non-productive time(NPT)greatly,resulting in inflating the drilling cost and also pose a safety *** of the main problems faced during drilling that limits the life of drilling equipment and tools and decreases the overall productivity of the system is drilling *** vibrations can be categorized into three modes:axial,lateral,and ***-slip vibrations are a type of torsional vibration in which the bottom hole assembly(BHA)periodically stops to rotate followed by a spike in the bottom hole *** paper provides a comprehensive review of techniques used to control and mitigate torsional vibration with an emphasis on stick-slip.A brief introduction to drillstring and friction modeling is presented followed by a concise summary of passive control techniques to control *** the focus is shifted to an up-to-date review of active control and machine learning for stick-slip control and *** paper ultimately highlights the importance of adapting novel control and mitigation concepts to improve stick slip detection and improve the overall drilling process.A unique solution is insufficient to control a complex process such as drilling,but integration of various techniques has been found promising.

关键词： Drilling vibrations Controllers Mitigations strategies Stick slip Torsional vibrations Machine Learning

Small-scale self-driving cars:A systematic literature review

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 271-292页

作者： felipe Caleffi Lauren da Silva Rodrigues Joice da Silva Stamboroski Brenda Medeiros Pereira Autonomous Vehicles Laboratory Federal University of Santa MariaCachoeira do Sul 96503-205Brazil Mobility and Logistics Laboratory Federal University of Santa MariaCachoeira do Sul 96503-205Brazil

The autonomous vehicle(AV)technology has the potential to significantly improve safety and efficiency of the transportation and logistics ***-scale AV testing is limited by time,space,and cost,while simulation-based testing often lacks the necessary accuracy of AV and environmental *** recent years,several initiatives have emerged to test autonomous software and hardware on scaled *** systematic literature review provides an overview of the literature surrounding small-scale self-driving cars,summarizing the current autonomous platforms deployed and focusing on the software and hardware developments in this *** studies published in English-language journals or conference papers that present small-scale testing of self-driving cars were *** of Science,Scopus,Springer Link,Wiley,ACM Digital Library,and TRID databases were used for the literature *** systematic literature search found 38 eligible *** gaps in the reviewed papers were identified to provide guidance for future *** key takeaway emerging from this manuscript are:(i)there is a need to improve the models and neural network architectures used in autonomous driving systems,as most papers present only preliminary results;(ii)increasing datasets and sharing databases can help in developing more reliable control policies and reducing bias and variance in the training process;(iii)small-scaled vehicles to ensure safety is a major benefit,and incorporating data about unsafe driving behaviors and infrastructure problems can improve the accuracy of predictive models.

关键词： Self-driving car Autonomous vehicle Small-scale vehicle Systematic literature review

Accuracy of tree mapping based on hand-held laser scanning comparing leaf-on and leaf-off conditions in mixed forests

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Journal of Forestry Research 2024年第5期35卷 14-25页

作者： Frederico Tupinambá-Simões Adrián Pascual Juan Guerra-Hernández Cristóbal Ordóñez Tiago de Conto felipe Bravo iuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIAValladolidSpain Department of Geographical Sciences University of MarylandCollege ParkMD 20742USA Forest Research Centre School of AgricultureUniversity of LisbonTapada da Ajuda1349‑017 LisbonPortugal

The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3D structures at high *** confirm the con-sistency in the retrieval of forest structural parameters using hand-held laser scanning(HLS),before operationalizing the method,confirming the data is *** analyzed the per-formance of tree-level mapping based on HLS under differ-ent phenology conditions on a mixed forest in western Spain comprising Pinus pinaster and two deciduous species,Alnus glutinosa and Quercus *** area was surveyed twice during the growing season(July 2022)and once in the deciduous season(February 2022)using several scan-ning *** reference data(418 trees,15 snags)was used to calibrate the HLS data and to assess the influence of phenology when converting 3D data into tree-level attrib-utes(DBH,height and volume).The HLS-based workflow was robust at isolating tree positions and recognizing stems despite changes in ***-six percent of all pairs matched below 65 *** DBH,phenology barely altered *** observed a strong agreement when comparing HLS-based tree height *** values exceeded 2 m when comparing height measurements,confirming height data should be carefully used as reference in remote sensing-based inventories,especially for deciduous *** volume was more precise for pines(r=0.95,and rela-tive RMSE=21.3–23.8%)compared to deciduous species(r=0.91–0.96,and relative RMSE=27.3–30.5%).HLS data and the forest structural complexity tool performed remark-ably,especially in tree positioning considering mixed forests and mixed phenology conditions.

关键词： Precision forestry Forest monitoring Mobile laser scanning Forest inventory

Histopathological impact of SARS-CoV-2 on the liver:Cellular damage and long-term complications

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World Journal of Gastroenterology 2024年第22期30卷 2866-2880页

作者： Alfonso Rodriguez-Espada Moises Salgado-de la Mora Briana Mariette Rodriguez-paniagua Nathaly Limonde la Rosa Monica Itzel Martinez-Gutierrez Santiago Pastrana-Brandes Nalu Navarro-Alvarez Department of Molecular Biology Universidad Panamericana School of MedicineCampus MéxicoMexico 03920Mexico Department of Internal Medicine Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico 14080Mexico Department of Surgery University of Colorado Anschutz Medical CampusDenverCO 80045United States PECEM Facultad de MedicinaUniversidad Nacional Autónoma de MéxicoMexico 04360Mexico Department of Gastroenterology Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico 14080Mexico

Coronavirus disease 2019(COVID-19),caused by the highly pathogenic severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),primarily impacts the respiratory tract and can lead to severe outcomes such as acute respiratory distress syndrome,multiple organ failure,and *** extensive studies on the pathogenicity of SARS-CoV-2,its impact on the hepatobiliary system remains *** liver injury is commonly indicated by reduced albumin and elevated bilirubin and transaminase levels,the exact source of this damage is not fully *** mechanisms for injury include direct cytotoxicity,collateral damage from inflammation,drug-induced liver injury,and ischemia/***,evidence often relies on blood tests with liver enzyme *** this comprehensive review,we focused solely on the different histopathological manifestations of liver injury in COVID-19 patients,drawing from liver biopsies,complete autopsies,and in vitro liver *** present evidence of the direct impact of SARS-CoV-2 on the liver,substantiated by in vitro observations of viral entry mechanisms and the actual presence of viral particles in liver samples resulting in a variety of cellular changes,including mitochondrial swelling,endoplasmic reticulum dilatation,and hepatocyte *** ly,we describe the diverse liver pathology observed during COVID-19 infection,encompassing necrosis,steatosis,cholestasis,and lobular *** also discuss the emergence of long-term complications,notably COVID-19-related secondary sclerosing *** the histopathological liver changes occurring during COVID-19 infection is pivotal for improving patient recovery and guiding decision-making.

关键词： Liver SARS-CoV-2 COVID-19 Angiotensin-converting enzyme 2 Histopathology Liver biopsies Liver autopsy In vitro

Geochemical elements in suspended particulate matter of Ensenada de La Paz Lagoon,Baja California Peninsula,Mexico:Sources,distribution,mass balance and ecotoxicological risks

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Journal of Environmental Sciences 2024年第2期136卷 422-436页

作者： Sandra Soledad Morales-García Pilar de Acacia Pérez-Escamilla Suresh Babu Sujitha Pichaimani Godwyn-Paulson Andrés felipe Zuniga-Cabezas Muthuswamy Ponniah Jonathan Instituto Politécnico Nacional(IPN) Centro Mexicano para la Producción más Limpia(CMPL)Av.Acueducto s/nCol.Barrio la Laguna TicománDel Gustavo A.MaderoC.P.07340Ciudad de MéxicoMexico Instituto Politécnico Nacional(IPN) Escuela Superior de Ingeniería y Arquitectura(ESIA)Unidad Ticomán***án 600Delg.Gustavo A.MaderoC.P.07340Ciudad de México(CDMX)Mexico Instituto Politécnico Nacional(IPN) Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y Desarrollo(CIIEMAD)Calle 30 de Junio de 1520Barrio la Laguna TicománDel.Gustavo A.MaderoC.P.07340Ciudad de MéxicoMéxico

The present study aimed to evaluate multi-element concentrations(Al,As,Ca,Cd,Co,Cr,Cu,Fe,Mg,Mn,Mo,Ni,Pb,Sr)in suspended particulate material(SPM)collected from Ensenada de La Paz(ELP)lagoon,Baja California Sur,Mexico in two different periods(September and May)to comprehend their origin,geochemical behavior,mass transfer and associated ecotoxicological *** 24 hr variation coefficient of volumetric SPM levels were found to be 51.7%in September and 40.5%in May,signifying the effects of oceanic *** calculated enrichment factor(EF)values for all the studied elements were of higher magnitude because of the high surface area and oxide nature of SPM,and in this study,Mo had the highest EF of 46.77 probably due to its origin from continental *** the ecotoxicological perspective,the integrated toxic risk index revealed low toxic risk to the benthic ***,the mean-ERM-Quotient calculated using the particulate concentrations of As,Cd,Cr,Cu,Ni,Pb indicated 9%probability of toxicity to *** comprehensive geochemical and ecotoxicological assessment of particulate metal concentrations in the ELP lagoon signify low to moderate contamination.

关键词： Suspended particulate material Heavy metals Risk assessment Mass transfer Ensenada de La Paz